This invention relates to reduction of malodour and concerns methods and compositions for reducing malodour.
It is clearly desirable to be able to reduce malodours in many circumstances, eg in domestic environments where common malodours include kitchen malodour, bathroom (lavatory) malodours, and malodours in carpets and furnishings eg caused by pets. Other common types of malodour include body malodour and malodours on clothes, eg caused by perspiration, smoke, environmental odours etc. The term xe2x80x9cmalodourxe2x80x9d is used to refer to smells or odours generally regarded as undesirable or unpleasant in nature.
It is well known to incorporate fragrance or perfume materials in a wide range of products such as kitchen and bathroom cleaning products, air fresheners, carpet and fabric cleaners, laundry products, personal hygiene products etc, with a view to reducing such malodours. See, for example, WO 97/07778 and EP 0780132.
The present invention is based on the surprising discovery that certain known perfume or fragrance materials, when used in admixture with one or more other perfume or fragrance materials, have a greater effect in reducing malodours than would be expected or predicted based on the effect in reducing malodours of the materials on their own, thus indicating the presence of a synergistic effect.
The perfume or fragrance materials concerned are as follows:
1. 5-methyl-2-(2-methylpropyl)-1,3-dioxane, which is described in WO 96/30359, and which will be referred to herein as xe2x80x9cCamonalxe2x80x9d or xe2x80x9cCamxe2x80x9d for brevity.
2. Methyl 1,4-dimethylcyclohexylcarboxylate, which is described in EP 0673408, and which will be referred to herein as xe2x80x9cCyprisatexe2x80x9d or xe2x80x9cCyxe2x80x9d for brevity.
3. 3-(((1-ethyloxy)ethyl)oxy)-3,7-dimethyl-1,6-octadiene, which is described in GB 1371727, and which will be referred to herein as xe2x80x9cElintaalxe2x80x9d or xe2x80x9cE1xe2x80x9d for brevity.
4. 7,9-dimethylspiro(5,5)undecan-3-one, which is described in EP 0074693, and which will be referred to herein as xe2x80x9cDispironexe2x80x9d or xe2x80x9cDisxe2x80x9d for brevity.
While these 4 materials are known to have attractive fragrance properties, their beneficial effect, when in admixture with other fragrance materials, in reducing malodours is not known and is not predictable.
In one aspect the present invention provides a fragrance composition comprising a mixture of two or more fragrance materials, including one or more of the following materials at least at the following minimum amounts by weight:
1. 5-methyl-2-(2-methylpropyl)-1,3-dioxane (Camonal) in an amount of at least 0.25%;
2. methyl 1,4-dimethylcyclohexylcarboxylate (Cyprisate) in an amount of at least 0.5%;
3. 3-(((1-ethyloxy)ethyl)oxy)-3,7-dimethyl-1,6-octadiene (Elintaal) in an amount of at least 15%; and
4. 7,9-dimethylspiro(5,5)undecan-3-one (Dispirone) in an amount of at least 2.5%.
In this specification, all references to % are % by weight unless otherwise specified.
The fragrance composition preferably includes at least two of the specified materials, preferably at least at the specified minimum amounts.
Camonal is preferably present at an amount of at least 7.5%. Cyprisate is preferably present in an amount in the range 0.5 to 15%. Elintaal is preferably present in an amount in the range 15 to 30%. Dispirone is preferably present in an amount of at least 2.5%.
There is a hedonic advantage in using mixtures as this allows a wider variety in fragrance hedonics to be produced with the same performance levels.
Mixtures containing 1:1:1 ratios of three of the ingredients perform well in all combinations. Mixtures containing 1:1 ratios of the ingredients should preferably contain Camonal or Cyprisate for good performance. Mixtures containing 1:1 ratios of Dispirone with an other ingredient should be avoided unless Camonal is used. Mixtures containing 2:1 ratios of ingredients perform best with either Canonal or Cyprisate at the highest proportion ingredient.
The terms xe2x80x9cfragrancexe2x80x9d and xe2x80x9cperfumexe2x80x9d are used synonymously in the present specification.
The terms xe2x80x9cfragrance materialxe2x80x9d or xe2x80x9cperfume materialxe2x80x9d are used herein to refer to a material which is added to a perfume or fragrance composition to contribute to the olfactive properties of the composition material. Typically, a perfume material will be generally recognised as possessing odours in its own right, will be relatively volatile and often has a molecular weight within the range 100 to 300. Typical perfume materials are described in xe2x80x9cPerfume and Flavour Chemicalsxe2x80x9d, Volumes I and II (Steffan Arctander, 1969).
The terms xe2x80x9cperfume compositionxe2x80x9d or xe2x80x9cfragrance compositionxe2x80x9d are used herein to mean a mixture of fragrance materials, if desired mixed with or dissolved in a suitable solvent or mixed with a solid substrate. The mixture may be a complex mixture of many ingredients. The composition may be used to impart a desired odour to the skin and/or any product for which an agreeable odour is indispensable or desirable. Examples of such products are: fabric washing powders, washing liquids, fabric softeners and other fabric care products; detergents and household cleaning, scouring and disinfection products; air fresheners, room sprays and pomanders; soaps, bath and shower gels, shampoos, hair conditioners and other personal cleansing products; cosmetics such as creams, ointments, toilet waters, preshave, aftershave, skin and other lotions, talcum powders, body deodorants and antiperspirants, etc.
Other fragrance materials which can advantageously be employed in the fragrance composition according to the invention are, for example, natural products such as extracts, essential oils, absolutes, resinoids, resins, concretes etc., but also synthetic materials such as hydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters, acetals, ketals, nitrites, etc., including saturated and unsaturated compounds, aliphatic, carbocyclic and heterocyclic compounds.
Such fragrance materials are mentioned, for example, in S. Arctander, Perfume and Flavor Chemicals (Montclair, N.J., 1969) in S. Arctander, Perfume and Flavor Materials of Natural Origin (Elizabeth, N.J., 1960) and in xe2x80x9cFlavor and Fragrance, Materialsxe2x80x941991xe2x80x9d, Allured Publishing Co. Wheaton, Ill. USA.
It is preferred that other fragrance materials used in the fragrance composition of the invention are themselves not particularly good at reducing malodour but have medium, neutral or poor performance in this regard. The presence of one or more of Camonal, Cyprisate, Elintaal and Dispirone in the composition improves the malodour reduction properties of the composition.
Examples of fragrance materials which can be used in fragrance compositions to the invention are: geraniol, geranyl acetate, linalol, linalyl acetate, tetrahydrolinalol, citronellol, citronellyl acetate, dihydromyrcenol, dihydromyrcenyl acetate, tetrahydro-myrcenol, terpineol, terpinyl acetate, nopol, nopyl acetate, 2-phenylethanol, 2-phenylethyl acetate, benzyl alcohol, benzyl acetate, benzyl salicylate, styrallyl acetate, benzyl benzoate, amyl salicylate, dimethylbenzyl-carbinol, trichloromethylphenylcarbinyl acetate, p-tert-butylcyclohexyl acetate, isononyl acetate, vetiveryl acetate, vetiverol, xcex1-hexylcinnamaldehyde, 2-methyl-3-(p-tert-butylphenyl)propanal, 2-methyl-3-(p-isopropyl-phenyl)propanal, 3-(p-tert-butylphenyl)-propanal, 2,4-dimethylcyclohex-3-enyl-carboxaldehyde, tricyclodecenyl acetate, tricyclodecenyl propionate, 4-(4-hydroxy4-methylpentyl)-3-cyclohexenecarboxaldehyde, 4-(4-methyl-3-pentenyl)-3-cyclohexenecarboxyaldehyde, 4-acetoxy-3-pentyltetrahydropyran, 3-carboxymethyl-2-pentyl-cyclopentane, 2-n-heptylcyclopentanone, 3-methyl-2-pentyl-2-cyclopentenone, n-decanal, n-dodecanal, 9-decenol-1, phenoxyethyl isobutyrate, phenyl-acetaldehyde dimethyl-acetal, phenylacetaldehyde diethylacetal, geranyl nitrile, citronellyl nitrile, cedryl acetate, 3-isocamphyl-cyclohexanol, cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine, heliotropin, coumarin, eugenol, vanillin, diphenyl oxide, hydroxycitronellal, ionones, methylionones, isomethylionones, irones, cis-3-hexenol and esters thereof, indan musks tetralin musks isochroman musks macrocyclin ketones, macrolactone musks, ethylene brassylate.
Solvents which can be used for fragrance compositions according to the invention are, for example: ethanol, isopropanol, diethyleneglycol monoethyl ether, dipropylene glycol, diethyl phthalate, triethyl citrate, isopropyl myristate, etc.
The fragrance composition may be in the form of a fragrance base, that is typically a mixture of many fragrance materials (up to, say, 50) intended to be mixed in use with a neutral complex fragrance. The resulting mixture also constitutes a fragrance composition in accordance with the invention, and may be intended to be used either as a fragrance in its own right or to impart desirable fragrance (and malodour reduction properties) to a product, typically a consumer product, eg as discussed above.
The present invention therefore also provides a product comprising a fragrance composition in accordance with the invention.
The fragrance composition is used in the product at a suitable level depending on the product, to achieve the desired effect in terms of fragrance and malodour reduction properties of the product, with typical levels being in the range 0.1 to 10% by weight.
In a further aspect, the invention also provides use of Camonal, Cyprisate, Elintaal and/or Dispirone in a perfume composition for enhancing the malodour reduction properties of the composition.
The invention also includes within its scope a method of enhancing the malodour reduction properties of a fragrance composition, comprising including in the composition at least one of Camonal, Cyprisate, Elintaal and Dispirone.
The present invention is concerned particularly with reduction of malodour (ie reducing the perceived intensity of a malodour) not by masking the malodour (eg dominating the malodour with a stronger odour) but by counteracting or neutralising the malodour in a way that reduces perceived malodour intensity without the need for an intense perfume, or a perfume with a pronounced idiosyncratic odour character such as eucalyptus or wintergreen: this is thought to involve some sort of blocking interaction, possibly between the chemical reagents involved, or in the nose or brain of a subject, although the mechanism is not understood.
The performance of materials in reducing malodour was measured experimentally by assessing materials on their own and in mixtures for their effectiveness in reducing (counteracting) standard malodours in small scale headspace assessments carried out by trained sensory assessors. Tests were preferably carried out using fragrance materials at similar intensity levels, ie at levels subjectively assessed by the trained assessors to have similar perceived levels of fragrance intensity (referred to herein as iso-intense fragrance levels), rather than using materials necessarily at the same amounts by weight, so that reduction in malodour is more likely to be due to malodour counteraction (either by chemical or sensory mechanisms) than to malodour masking (by a fragrance material of stronger intensity).
The invention will be further described, by way of illustration, in the following Examples.
Techniques have been developed for the accurate measurement of the performance of fragrance materials and compositions against standard malodours utilising small scale headspace assessments carried out by a sensory panel of trained sensory assessors.
The sensory panel consists of a pool of between 25 and 35 members, who are all screened and then trained over a period of 6 months. Training includes learning to identify individual odour characters in complex mixtures, and to score their perceived intensity using a ratio scoring technique (Magnitude Estimation). The level of efficiency of the panel is continuously monitored to ensure a high level of accuracy and reproducibility.
During testing all variables other than those actually under test are controlled as carefully as possible. Samples are always prepared so that they are, as far as possible, identical apart from their differences in odour. When presented to panellists they are presented in random order and given random 3-figure codes. A minimum of 28 assessments were collated for each sample.
All assessments reported in the examples were carried out in a purpose built panel suite. The suite is designed so that all external distractions (ie. odour, noise, movement) are eliminated, and the panellists are not distracted during testing.
The perfume material and malodour are placed alongside each other in a 500 ml glass vessel: 3 ml of malodour in a squat 15 ml jar alongside a perfume material (1 ml in a 15 ml upright jar). The vessel is closed and allowed to equilibrate for half an hour before assessment.
The malodours are selected for practical usefulness. Standard malodours have been identified which would be suitable. In these examples a bathroom malodour was used.
Each panel member assesses each sample for the intensity of malodour and perfume material that can be perceived in the headspace of the glass vessel. Hidden blanks (malodour but no perfume) are included as internal controls. The scores for each of the panellists are normalised and averaged to give a consensus score across the whole panel.
Standard statistical techniques are employed to compare the performance of each perfume material against the malodour and the statistical significance of any differences detected. A performance value for each ingredient when tested in mixtures was calculated using the general linear models procedure (PROC REG) of the Statistical Analysis System (SAS). The SAS system is an integrated system of software developed by the SAS Institute Inc, SAS Campus Drive, Cary, N.C. 27514,USA. SAS is a registered Trade Mark. The REG procedure is a general purpose procedure fitting linear regression models by the method of least squares.